Finally, the CF CSL Airbox goes in.


So I received my CSL air box in January of this year. I did not want to install it when the weather was crappy, just due to the fact that i hate working in the cold and wanted to do it on a nice day. Today was that day. I spent the past few days reviewing the DIY that enigmaticdream created and the Group Buy thread, which has plenty of information for someone to complete this install.

Before I began I purchased a few things.

-10 1 3/4 – 2 3/4 hose clamps from Home Depot – $10
-Lisle 30500 CV Boot Clamp Plier = $17 on
-OEM BMW Throttle Position Sensor (i replaced the front one a few years ago, the rear one located under the intake manifold is on its original so I thought I would replace it) – $80 from

After that, i just dove right in. I got to my garage at 930am. I took my time, had help from Lightwerkz, and bs’ed a lot and got out by 3pm.

I am going to post some pictures and go through the process.


I removed the strut bar center, the battery cables, the cabin filter, and some of the weather stripping around the ecu box area.


Although the other DIY indicates to not worry about using the Lisle boot clamp tool, I enjoyed using it. Made removing the clamps simple. All you do is hook up one hook on each tooth of the clamp remover.


Ok, this is something that wasn’t included in the other DIY, maybe it was, but I didn’t read it well enough. So the runners from the intake manifold connect to the throttle bodies. Once you remove the clamps, the 2 hoses on top of the intake manifold, the 2 hoses under the intake manifold, and the bunch of hoses that are hooked onto a tab under the manifold, you have to remove 2 10mm bolts that hold the manifold to a v-shaped frame. Once that is removed, you unscrew the runners off the intake manifold. Once you do that, you can remove the plastic threaded portion found in EnigmaticDreams DIY.

Here is the threaded portion:

threaded plastic

This is me removing the clamp off the runners after they were screwed OFF the intake manifold:


Once everything was removed I got to look at this:



Initially I wanted to buy some throttle body cleaner and clean them out, but they looked fine when I inspected them. Not much build up. I also noticed there was NO oil leak what-so-ever anywhere, which was a relief.

The next part was the most annoying thing I have ever dealt with. The Dipstick. I do not remember, but I thought I had paid for the CSL dipstick. But this was a PITA. Essentially you have to bend the dipstick so that the red handle is behind the strut bar. It took lots of time, but eventually we got it bent the right way.

Here is where it sits:




Another thing with the dipstick, I removed the 8mm bolt that holds down a clamp. Then pulled the dipstick upwards. THere was a gasket that was in the hole, that I dropped and didn’t find. I replaced it with a copper gasket that fit quite well. Its really strange how simple it is to remove the dipstick. The end of the dipstick has a lip which acts as a gasket as well.

I also bent the bracket on the dipstick that normally is used to be held on to the oem intake manifold. As it sits, its quite stable and doesn’t move. So no banging onto the CF goodness.

Once that was done, I took the air box and undid the 3 allen bolts that hold on the small part of the intake to the big part. I then took the rubber runners and slid them onto the throttle bodies. I used the home depot clamps to hold the rubber on the throttle bodies side and then slid the hose clamps Evolve gave me on the wider rubber part that would hold the CF runners.


Next is this hose that hooks up to the intake manifold on the far right on the top. This connects to a hose near the ECU. I shimmied a flat head into the rubber portion, and pulled the hose out hard. This is a perfect fit into the CF air box.


Once I slid the air box in, I connected all the hoses. I then slowly tightened the hose clamps. Next up was the Evolve air filter. It was extremely oily when I removed the filter. It snapped in quite easily.



After that was done, it was time to see if that dipstick bending was successful. The second part of the air box uses tabs to slide the big part into the little part on the bottom, a tab on the side near the firewall, and just the allen screws on the top and the side near the front of the air box. It took some maneuvering, and loosening up the hose clamps to get the air box to slide in together. Once in, tighten the 3 allen head screws and voila the air box is installed.


The method I chose for wiring was to cut the MAF sensor off and just solder in the IAT wiring that Evolve supplied. Lightwerkz did my wiring and did a fantastic job. Soldered the wiring and heat shrink wrapped the remaining wires exposed wires.



The only issue that I have is that the threading for the IAT was full of resin so it did not screw down all the way. Its in halfway, but my opinion is as long as the sensor is in the hole fully, we should be fine. I am sure the threaded portion just acts like a seal.


Causes for concern:

-like others mentioned – the rubber boots do bunch up a bit. I guess thats just the nature of hose clamps. they are tightly holding the throttle bodies and cf runners, so it should be nice.

-the holes that hold the bracket on the bottom of the air box. they were filled with resin. it made screwing the nuts evolve supplied a scare since you didn’t want to cross thread them nor did you want to crack the air box.

-the hole for the IAT, same issue, resin in the thread.

-the plastic housing that holds the upper radiator hose. It rubs against the front of the air box. I need to put some electric tape or something to stop it from doing more damage:


Here are some pictures of the air box installed:





My car is completely gutted. The only thing remaining in the car are seats, front door panels, a roll bar, and a dash. I also have spherical bushings everywhere and a race suspension. So the car is naturally loud. Before this air box I had an AFE Stage 2 intake which made a significantly better sound than the OEM air box. With that being said, I can hear the CF CSL air box above 5500rpm and below 3000rpm. From 3100-4900rpm, the sound of the car is too overwhelming that I don’t notice a difference.

I am sure that the air box makes a HUGE difference from the outside of the car, but from the inside, the car is so hollow and gutted that its not that noticeable. I would go as far as saying it is not as day and night or as obvious as the Top Gear CSL video makes it out to be. Perhaps it needs more time to adapt and will start sounding that much better.

I do feel at the top end the intake sounds great. The car is just so loud on the inside when I drive it, its hard for me to recognize. I ripped it a few times to 8100rpm and it sounded great. Also, taking off in first gear, you can hear the growl of induction. I need more time with it really.

Now what I do feel is the Alpha N Tune. Evolve does a great job with the ease of flashing the tune with their Evolve-R Tuning cable and software. I ran into an issue since I did not have the updated software, but I got lucky and downloaded it. The tune flashed SO quickly and easily. Turned the car on and it fired right up. I gave it some gas and it stuttered hard and then fell on its face and it stalled. Turned it on, left it running for about 3-5 minutes and the car was good to go!

The car pulls nicely w/the alpha N tune. What I immediately noticed was shifting from 1st to 2nd. There seemed to be more torque. Perhaps the torque curve got even flatter and maybe got a few more lbs-tq. I think the top end power is also slightly improved. Perhaps 10hp or so. We will find out when I get the car dyno’ed this summer.


The Evolve Carbon Fiber CSL Airbox is great. Its a quality made piece and looks fantastic. I really love the 1×1 gloss. I am glad I went with it. The causes of concern are the resin in the threaded areas, but those are minute. The dipstick is a pita to bend. If I did it over again, I would have opted for the CSL dipstick. I love the alpha n tune. I think it adds more power and feels great. I want to drive the car more so it adapts more and I can give a better review.

I plan on making a video in a few days of in car and hopefully a drive by so you can hear the howl. Until then, enjoy the pictures. Thanks for reading.

2 thoughts on “Finally, the CF CSL Airbox goes in.

  1. Nice review bro and congrats for getting it all installed. The 1×1 Gloss looks incredible.

    I can’t wait to finally get my Airbox installed!

    Keep us all posted bro.

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